How to add .gitignore file into Xcode project

Question

When making sure that iPhone project could be installed as an exact copy into a brand new computer via version control (git), I just realized that .gitignore

Answer 1

This solution didn't work for me in XCode 8.0 and El Capitan.

I opened a terminal and typed:

defaults write com.apple.finder AppleShowAllFiles YES
cd ../PATH_TO_GIT_ROOT 
touch .gitignore

Then relaunched Finder and my .gitignore file was visible. Edit per .gitignore documentation